Doorbell



FIG. 1 is a front perspective view of a preferred embodiment of the doorbell according to the present design;

FIG. 2 is a front elevational view of the doorbell of FIG. 1;

FIG. 3 is a rear elevational view of the doorbell of FIG. 1;

FIG. 4 is a right-side elevational view of the doorbell of FIG. 1, the left-side elevational view being a mirror image thereof;

FIG. 5 is a top plan view of the doorbell of FIG. 1; and,

FIG. 6 is a bottom plan view of the doorbell of FIG. 1.

The broken lines depict unclaimed environmental subject matter. 

CLAIM The ornamental design for a doorbell, as shown and described. 